Risk of stroke and coronary heart disease among various levels of blood pressure in diabetic and nondiabetic Chinese patients

OBJECTIVE: To compare the risk of stroke and coronary heart disease (CHD) among various blood pressure (BP) levels in diabetic and people without diabetes Chinese patients. METHODS: This cross-sectional study was part of Prospective Urban Rural Epidemiology China study. Patients aged 35 to70 years were recruited from 12 provinces of China between 2005 and 2009. The participants were classified into three groups: hypertension (HTN), high normal BP, and normal BP, and also into SBP and DBP quintiles. RESULTS: A total of 42 959 patients were analyzed with 38 975 (90.7% of total population) people without diabetes and 3984 (9.3% of total population) diabetic patients. Among diabetic patients, the HTN group was associated with an increased risk of stroke (odds ratio, 3.03; 95% confidence interval, 1.47-6.25) and CHD (odds ratio, 2.21; 95% confidence interval, 1.45-3.38), when compared with normal BP group. Similar results were drawn in nondiabetic patients. However, no significant difference in risk of stroke or CHD was found between high normal BP and normal BP groups in either diabetic or nondiabetic patients. Risk of CHD and stroke increased significantly when SBP was above 125 mmHg or DBP above 72 mmHg in people without diabetes, whereas this trend was attenuated in diabetic patients. CONCLUSION: HTN was associated with a two-fold increased risk of CHD and a three-fold increased risk of stroke compared with normotension irrespective of diabetes status. For diabetic patients with HTN, a more comprehensive method is essential for assessing cardiovascular risk.